Merge branch 'master' of github.com:brynary/arel

* 'master' of github.com:brynary/arel:
  use subquery for limit when DISTINCT is used (in Oracle)
  added missing require 'spec_helper' in crud_spec.rb

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/arel/visitors/oracle.rb b/lib/arel/visitors/oracle.rb
index 659b75f16d..c691ce294e 100644
--- a/lib/arel/visitors/oracle.rb
+++ b/lib/arel/visitors/oracle.rb
@@ -6,7 +6,9 @@ module Arel
       def visit_Arel_Nodes_SelectStatement o
         o = order_hacks(o)
 
-        if o.limit && o.orders.empty? && !o.offset
+        # if need to select first records without ORDER BY and GROUP BY and without DISTINCT
+        # then can use simple ROWNUM in WHERE clause
+        if o.limit && o.orders.empty? && !o.offset && o.cores.first.projections.first !~ /^DISTINCT /
           o.cores.last.wheres.push Nodes::LessThanOrEqual.new(
             Nodes::SqlLiteral.new('ROWNUM'), o.limit
           )
@@ -31,7 +33,7 @@ module Arel
           eosql
         end
 
-        if o.limit && !o.orders.empty?
+        if o.limit
           o       = o.dup
           limit   = o.limit
           o.limit = nil